Drive apparatus adapted to promote heat dissipation from electronic circuit integrated therein
Summary by NHIP
Drive apparatus with internal circuit
The drive apparatus integrates an electronic circuit containing a semiconductor module, capacitor, and choke coil within a motor assembly. The capacitor sits radially inside a heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
Claim Score by NHIP
Abstract
A drive apparatus has a motor device having a tubular motor case. A stator is arranged radially inside the motor case. A rotor is arranged radially inside the stator. A shaft is rotatable with the rotor. An electronic circuit is arranged in the central axis direction of the shaft relative to the motor case. A choke coil has a hole in a central part thereof, in which the shaft is inserted.

Term
Projected expiry 8 February 2031.
- Priority
- Filed
- Granted
- Today
- Projected expiry
49 claims: 6 independent, 43 dependent
- 1A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;and an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module, wherein the choke coil has a hole in a central part thereof and is arranged with an axial end of the shaft passing therethrough, the axial end being opposite to another axial end of the shaft, from which rotary torque of the motor is output to an external side of the motor, and wherein the capacitor is arranged radially inside the heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
- 9A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;and an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module, wherein the choke coil has a hole in a central part thereof and is arranged with the shaft passing therethrough, wherein the choke coil and the semiconductor module are arranged side by side in a direction perpendicular to the central axis of the shaft and in a radial direction of he motor case, and wherein the capacitor is arranged radially inside the heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
- 17A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;and an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module, wherein the motor has a heat sink, which extends in the axial direction of the shaft from one axial end part of the motor case and is formed near a radially outside part of the choke coil, wherein the semiconductor module is arranged on a side wall of the heat sink, and wherein the choke coil has a hole in a central part thereof and is arranged with the shaft passing therethrough.
- 26Broadest claimClaim Score 44, average(NHIP)A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module;and a rotation detection sensor for detecting rotation of the shaft, wherein the choke coil has a hole in a central part thereof, is arranged with the shaft passing therethrough, and is positioned away from the rotation detection sensor not to influence magnetic field of the rotation detection sensor, and wherein the capacitor is arranged radially inside the heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
- 34A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module, wherein the motor has a heat sink, which extends in the central axis direction of the shaft from one axial end part of the motor case and has a cut part formed partly in the central axis direction of the shaft, wherein the semiconductor module is arranged on a side wall of the heat sink, wherein the choke coil has a hole in a central part thereof and is arranged with the shaft passing therethrough, and wherein the capacitor is arranged radially inside the heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
- 42A drive apparatus comprising:a motor, which has a cylindrical motor case, a stator, a rotor and a shaft, the stator being arranged radially inside the motor case and wound with coils of a plurality of phases, the rotor being arranged radially inside the stator, and the shaft being rotatable with the rotor;an electronic circuit, which has a semiconductor module, a capacitor and a choke coil, the semiconductor module being arranged in a central axis direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases, the capacitor being connected in parallel to a power line and a ground line of the semiconductor module, and the choke coil provided in the power line of the semiconductor module, wherein the semiconductor module is a part of a semiconductor module unit of a plurality of semiconductor modules, which is linked by a bus bar, wherein the choke coil has a hole in a central part thereof and is arranged with the shaft passing therethrough, and wherein the capacitor is arranged radially inside the heat sink to face the semiconductor module through the heat sink in a radial direction of the shaft.
Independent claims6
98 paragraphs in 6 sections, as filed
CROSS REFERENCE TO RELATED APPLICATION
This application is based on and incorporates herein by reference Japanese Patent Application No. 2009-149645 filed on Jun. 24, 2009.
FIELD OF THE INVENTION
The present invention relates to a drive apparatus such as an electronic circuit-integrated motor device, in which an electronic circuit is integrated.
BACKGROUND OF THE INVENTION
An electric power assist system, which generates torque electrically, is used more and more in recent years as a mechanism for assisting the steering operation of a steering wheel of a vehicle. As an electric motor as a power generation source of the electric power assist system, a brushless motor is used for example. The brushless motor is driven to rotate by application of three-phase alternating currents. It is necessary to generate the alternating currents of different phases from a direct current power source of a predetermined voltage (for example, 12 volts) so that coil currents of different phases are supplied to coils of a plurality of phases (for example three phases). An electronic circuit is thus needed to switch over the coil currents. The electronic circuit includes a semiconductor module, a noise filtering aluminum electrolytic capacitor, a noise filtering choke coil, a microcomputer and the like. A semiconductor chip, which performs the switching operation, is integrated within the semiconductor module. It is proposed to arrange the electronic circuit near the motor (for example, patent document 1). <ul><li id="ul0001-0001" num="0004">Patent document: JP 2002-345211A</li></ul>
A comparatively large motor is normally used in the electric power assist system to provide sufficient torque. Further, a large aluminum electrolytic capacitor and a choke coil are normally provided on the electronic circuit to protect the semiconductor module from being broken by surge voltages generated by the current switching operation and to reduce electric power source noise.
A variety of systems are also provided recently in a vehicle in addition to the electric power assist system. These systems need respective spaces in the vehicle to be mounted. The motor itself of the electric power assist system is thus required to be smaller in size. According to the motor disclosed in the patent document 1, the semiconductor module and electronic parts such as the aluminum electrolytic capacitor are arranged in the axial direction of the motor.
The choke coil has a comparatively large volume and occupies a large space in case it is mounted on a printed circuit board of the electronic circuit. Even if the choke coil is ring-shaped and arranged perpendicularly to the printed circuit board, it is likely that its winging becomes non-uniform partly and magnetic field leaks. The choke coil is provided in a power cable of the semiconductor module. Since a large current flows in the choke coil, the choke coil must be arranged to promote heat dissipation.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a drive apparatus, which integrates therein an electronic circuit including a choke coil and promotes heat dissipation of the choke coil.
According to the present invention, a drive apparatus comprises a motor and an electronic circuit. The motor has a cylindrical motor case, a stator, a rotor and a shaft. The stator is arranged radially inside the motor case and wound with coils of a plurality of phases. The rotor is arranged radially inside the stator. The shaft is rotatable with the rotor. The electronic circuit has a semiconductor module, a capacitor and a choke coil. The semiconductor module is arranged in the axial direction of the shaft relative to the motor case and configured to switch over coil currents flowing in the coils of the plurality of phases. The capacitor is connected in parallel to a power line and a ground line of the semiconductor module. The choke coil is provided in the power line of the semiconductor module. The choke coil has a hole in a central part thereof and the shaft is inserted into the choke coil.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings:
<figref idrefs="DRAWINGS">FIG. 1</figref> is an electric circuit diagram showing an electric power steering system;
<figref idrefs="DRAWINGS">FIG. 2</figref> is a top plan view showing a drive apparatus, which is used in the electric power steering system, according to the first embodiment of the present invention;
<figref idrefs="DRAWINGS">FIG. 3</figref> is a side view showing the drive apparatus according to the first embodiment, which is viewed in the direction K in <figref idrefs="DRAWINGS">FIG. 2</figref>;
<figref idrefs="DRAWINGS">FIG. 4</figref> is a cross-sectional view showing the drive apparatus according to the first embodiment, which is taken along the line IV-IV in <figref idrefs="DRAWINGS">FIG. 3</figref>;
<figref idrefs="DRAWINGS">FIG. 5</figref> is a perspective view showing the drive apparatus according to the first embodiment;
<figref idrefs="DRAWINGS">FIG. 6</figref> is an exploded perspective view showing the drive apparatus according to the first embodiment;
<figref idrefs="DRAWINGS">FIGS. 7A</figref>, <b>7</b>B and <b>7</b>C are a plan view, a side view and a perspective view showing a choke coil used in the drive apparatus according to the first embodiment;
<figref idrefs="DRAWINGS">FIG. 8</figref> is a diagram showing the history of development of a motor device;
<figref idrefs="DRAWINGS">FIG. 9</figref> is a top plan view showing a drive apparatus according to the second embodiment of the present invention;
<figref idrefs="DRAWINGS">FIG. 10</figref> is a perspective view showing the drive apparatus according to the second embodiment;
<figref idrefs="DRAWINGS">FIGS. 11A</figref>, <b>11</b>B and <b>11</b>C are a plan view, a side view and a perspective view showing a choke coil used in the drive apparatus according to the second embodiment;
<figref idrefs="DRAWINGS">FIG. 12</figref> is a top plan view showing a drive apparatus according to the third embodiment of the present invention;
<figref idrefs="DRAWINGS">FIG. 13</figref> is a perspective view showing the drive apparatus according to the third embodiment of the present invention; and
<figref idrefs="DRAWINGS">FIGS. 14A</figref>, <b>14</b>B and <b>14</b>C are a plan view, a side view and a perspective view showing a choke coil used in the drive apparatus according to the third embodiment;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
First Embodiment
An electronic circuit-integrated motor device according to the first embodiment is provided for an electric power assist system such as an electric power steering system (EPS system), which is a power assist system exemplified in <figref idrefs="DRAWINGS">FIG. 1</figref>.
Referring first to <figref idrefs="DRAWINGS">FIG. 1</figref>, a drive apparatus <b>1</b> includes a motor <b>30</b>, a power circuit <b>50</b> and a control circuit <b>70</b>. The drive apparatus <b>1</b> provides steering assist to a steering wheel <b>91</b> of a vehicle by generating a rotary torque for a column shaft <b>92</b> through a gear <b>93</b> mounted on the column shaft <b>92</b>, which is a rotating shaft of the steering wheel <b>91</b>. More specifically, when the steering wheel <b>91</b> is operated by a driver, a torque sensor <b>94</b> detects a steering torque that is generated for the column shaft <b>92</b> as a result of steering. Further, a vehicle speed signal is acquired from a CAN (controller area network), which is not shown, to provide steering assist to a driver who steers the steering wheel <b>91</b>. The use of this mechanism, depending on the employed control method, will make it possible not only to provide steering assist, but also to provide automatic control of operations of the steering wheel <b>91</b> for the purpose, for instance, of causing the vehicle to stay in a traffic lane on an expressway or guiding the vehicle into a parking space in a parking lot.
The motor <b>30</b> is a brushless motor that rotates the gear <b>93</b> in a normal direction and in a reverse direction. The power circuit <b>50</b> supplies electrical power to the motor <b>30</b>. The power circuit <b>50</b> includes a choke coil <b>52</b>, which is positioned in a power supply cable from a power source <b>51</b>, a shunt resistor <b>55</b>, and an inverter circuit <b>60</b>.
The inverter circuit <b>60</b> includes seven metal oxide semiconductor field effect transistors (MOSFETs) <b>61</b>, <b>62</b>, <b>63</b>, <b>64</b>, <b>65</b>, <b>66</b>, <b>67</b>, which are classified as one of a variety of types of field effect transistors. The MOSFETs <b>61</b> to <b>67</b> are switching elements. More specifically, the path between the source and drain of each MOSFET turns on (closes) or off (opens) depending on the electric potential applied to the gate.
The MOSFETs <b>61</b> to <b>67</b> are hereinafter referred to as FETs <b>61</b> to <b>67</b>, respectively. The FET <b>67</b>, which is connected most closely to the shunt resistor <b>55</b> serves as a power relay that prevents an electrical current from flowing in a reverse direction when the power source <b>51</b> is erroneously connected in polarity.
The drains of the three FETs <b>61</b> to <b>63</b> are connected to the power supply cable side, that is, high potential side. The sources of the FETs <b>61</b> to <b>63</b> are connected to the drains of the remaining three FETs <b>64</b> to <b>66</b> at the low potential side, respectively. The gates of the six FETs <b>61</b> to <b>66</b> as well as the gate of the FET <b>67</b> are connected to output terminals of a pre-driver circuit <b>71</b>. Three connection points (junctions) between the series-connected FETs among FETs <b>61</b> to <b>66</b> are respectively connected to a U-phase coil, a V-phase coil, and a W-phase coil of the motor <b>30</b>.
In the following description, if necessary, the FETs <b>61</b> to <b>66</b> are referred to as FET (Su+) <b>61</b>, FET (Sv+) <b>62</b>, FET (Sw+) <b>63</b>, FET (Su−) <b>64</b>, FET (Sv−) <b>65</b> and FET (Sw−) <b>66</b>, respectively.
An aluminum electrolytic capacitor <b>56</b> is connected in parallel between the power supply cable of the FET (Su+) <b>61</b> and the ground of the FET (Su−) <b>64</b>. Similarly, an aluminum electrolytic capacitor <b>57</b> is connected in parallel between the power supply cable of the FET (Sv+) <b>62</b> and the ground of the FET (Sv−) <b>65</b>. An aluminum electrolytic capacitor <b>58</b> is connected in parallel between the power supply cable of the FET (Sw+) <b>63</b> and the ground of the FET (Sw−) <b>66</b>. Each of the aluminum electrolytic capacitors <b>56</b> to <b>58</b> are simply referred to as the capacitor.
The control circuit <b>70</b> includes the pre-driver circuit <b>71</b>, a customized integrated circuit (custom IC) <b>72</b>, a position sensor <b>73</b> and a microcomputer <b>74</b>. The custom IC <b>72</b> includes three functional blocks, that is, a regulator circuit <b>75</b>, a position sensor signal amplifier circuit <b>76</b> and a detected voltage amplifier circuit <b>77</b>.
The regulator circuit <b>75</b> is a stabilization circuit that stabilizes the power source voltage. The regulator circuit <b>75</b> stabilizes the supply of electrical power to various units. For example, the regulator circuit <b>75</b> ensures that the microcomputer <b>74</b> operates on a predetermined stabilized supply voltage (e.g., 5 V).
The position sensor signal amplifier circuit <b>76</b> inputs a signal from the position sensor <b>73</b>. The position sensor <b>73</b> is provided in the motor <b>30</b> and outputs a rotational position signal of the motor <b>30</b>. The position sensor signal amplifier circuit <b>76</b> amplifies the rotational position signal and outputs the amplified rotational position signal to the microcomputer <b>74</b>.
The detected voltage amplifier circuit <b>77</b> detects a voltage across the shunt resistor <b>55</b> installed in the power circuit <b>50</b>, amplifies the detected voltage indicative of the coil current supplied to the motor <b>30</b>, and outputs the amplified voltage to the microcomputer <b>74</b>.
Consequently, the rotational position signal of the motor <b>30</b> and the voltage across the shunt resistor <b>55</b> are applied to the microcomputer <b>74</b>. A steering torque signal is also applied to the microcomputer <b>74</b> from the torque sensor <b>94</b> mounted on the column shaft <b>92</b>. In addition, the vehicle speed signal is inputted to the microcomputer <b>74</b> through the CAN.
Upon receipt of the steering torque signal and the vehicle speed signal, the microcomputer <b>74</b> controls the inverter circuit <b>60</b> through the pre-driver circuit <b>71</b> in accordance with the rotational position signal and in such a manner as to provide steering assist to the steering wheel <b>91</b> in accordance with vehicle speed. More specifically, the inverter circuit <b>60</b> is controlled by turning on or off the FETs <b>61</b> to <b>66</b> through the pre-driver circuit <b>71</b>. As the gates of the six FETs <b>61</b> to <b>66</b> are connected to the six output terminals of the pre-driver circuit <b>71</b>, the pre-driver circuit <b>71</b> changes the potentials of the gates.
Further, the microcomputer <b>74</b> controls the inverter circuit <b>60</b> in accordance with the voltage across the shunt resistor <b>55</b>, which is input from the detected voltage amplifier circuit <b>77</b>, so that the electrical current is supplied to the motor <b>30</b> in generally a sine wave form.
The choke coil <b>52</b> is provided to suppress power source noise. The capacitors <b>56</b> to <b>58</b> store electric charge therein to assist power supply to the FETs <b>61</b> to <b>66</b> and suppress noise components such as surge voltages. Since the FET <b>67</b> is provided for protection from reverse connection of the power source <b>51</b>, the capacitors <b>56</b> to <b>58</b> will not be damaged or broken even when the power source <b>51</b> is erroneously connected.
For controlling the operation of the motor <b>30</b>, the power circuit <b>50</b> and a control circuit <b>70</b> are provided. The power circuit <b>50</b> and the control circuit <b>70</b> are configured as an electronic control unit (ECU). The drive apparatus <b>1</b> has a unique integrated configuration of the ECU.
The motor <b>30</b> used in the EPS has its output power of about 200 W to 500 W. The power circuit <b>50</b> and the control circuit <b>70</b> occupy physically about 20% to 40% of space in the drive apparatus <b>1</b>. Since the output power of the motor <b>30</b> is large, the power circuit <b>50</b> correspondingly becomes large and occupies more than 70% of the total area of the power circuit <b>50</b> and the control circuit <b>70</b>.
Among parts forming the power circuit <b>50</b>, the choke coil <b>52</b>, the capacitors <b>56</b> to <b>58</b> and the semiconductor modules <b>51</b> to <b>53</b> including the FETs <b>61</b> to <b>67</b> occupy more than 70% of the area of the power circuit <b>50</b> and the control circuit <b>50</b>.
The FET <b>67</b>, which is for protection from reverse connection, the FET (Su+) <b>61</b> and the FET (Su−) <b>64</b> are configured as semiconductor chips. These semiconductor chips are resin-molded in one semiconductor module <b>501</b>. The FET (Sv+) <b>62</b> and FET (Sv−) <b>65</b> are also configured as semiconductor chips. These semiconductor chips are resin-molded in one semiconductor module <b>502</b>. The FET (Sw+) <b>63</b> and FET (Sw−) <b>66</b> are also configured as semiconductor chips. These semiconductor chips are resin-molded in one semiconductor module <b>503</b>.
The inverter circuit <b>60</b> is thus configured by three semiconductor modules <b>501</b> to <b>503</b>. In this embodiment, although only one inverter circuit <b>60</b> is shown, another inverter circuit is provided so that the current, which flows in each inverter circuit <b>60</b> is reduced to one-half. Since two inverter circuits <b>60</b> are used, six semiconductor modules <b>501</b> to <b>506</b> and six capacitors <b>701</b> to <b>706</b> are provided as shown in <figref idrefs="DRAWINGS">FIG. 2</figref>.
As best shown in <figref idrefs="DRAWINGS">FIG. 4</figref>, the drive apparatus <b>1</b> has a motor housing that includes a tubular motor case <b>103</b> made of metal; an end frame <b>102</b>, which is screw-fastened to one axial end of a cylindrical part <b>1032</b> of the motor case <b>103</b>; and a cover <b>104</b>, which is in a bottomed cylindrical shape fitted over the other axial end of the cylindrical part <b>1032</b> of the motor case <b>103</b> to cover the electronic circuit part therein. An electric connector (not shown) for connection to the power source <b>51</b> is attached to the cover <b>103</b>.
The motor <b>30</b> also has a stator <b>201</b> positioned on the radially inside part of the cylindrical part <b>1032</b> of the motor case <b>103</b>, a rotor <b>301</b> positioned in the radially inside part of the stator <b>201</b>, and a shaft <b>401</b> made of metal and fit firmly in the rotor <b>301</b> to rotate together with the rotor <b>301</b>.
The motor case <b>103</b> has, in addition to the cylindrical part <b>1032</b> for fixing the stator <b>201</b>, a partition wall <b>1031</b> extending radially inward from the axial end of the cylindrical part <b>1032</b>. The partition wall <b>1031</b> partitions the stator <b>201</b> and the rotor <b>301</b> from the outside.
The stator <b>201</b> includes twelve salient poles <b>202</b>, which protrude in the radially inward direction from the inner side wall of the cylindrical part <b>1032</b>. The salient poles <b>202</b> are disposed at predetermined angular intervals in the circumferential direction of the cylindrical part <b>1032</b>. The salient poles <b>202</b> each include a multi-layer core <b>203</b>, which is formed by a stack of thin magnetic plates, and an insulator <b>204</b>, which fits with the axially outer end of the multi-layer core <b>203</b>. Coils (windings) <b>205</b> are wound on the insulator <b>204</b>. Each of the coils <b>205</b> is a three-phase winding of a U-phase, a V-phase or a W-phase and has two sets of U-phase, V-phase or W-phase. The coils <b>205</b> of each set are connected in Δ-shape, for instance. A lead wire <b>206</b> of each coil <b>205</b> is taken out from six holes provide in the partition wall <b>1031</b> of the motor case <b>103</b>. As described later and shown in <figref idrefs="DRAWINGS">FIGS. 4 and 5</figref>, the lead wires <b>206</b> are routed from the partition wall <b>1031</b> of the motor case <b>103</b> to the radially outside part of the semiconductor modules <b>501</b> to <b>506</b>.
The rotor <b>301</b> is made, for instance, of iron or other magnetic materials and formed into the tubular shape. The rotor <b>301</b> includes a rotor core <b>302</b> and permanent magnets <b>303</b> that are fixed to the radially outside part of the rotor core <b>302</b>. The magnets <b>303</b> are magnetized in N-pole and S-pole alternately in the circumferential direction of the rotor <b>301</b>.
The shaft <b>401</b> is fixedly fastened to a shaft hole <b>304</b> formed at the axial and radial center of the rotor core <b>302</b>. The shaft <b>401</b> is rotatably supported by a bearing <b>105</b> in the partition wall <b>1031</b> of the motor case <b>103</b> and by a bearing <b>106</b> in the end frame <b>102</b>. This ensures that the shaft <b>401</b> can rotate together with the rotor <b>301</b> with respect to the stator <b>201</b>. The shaft <b>401</b> passes through the choke coil <b>52</b>, which has a ring shape as illustrated in <figref idrefs="DRAWINGS">FIG. 2</figref> and more specifically a cylinder shape as illustrated in <figref idrefs="DRAWINGS">FIG. 6</figref>, and extends toward the printed circuit board <b>801</b> of the control circuit <b>70</b>. The axial end of the shaft <b>401</b> that is positioned closely to the printed circuit board <b>801</b> is provided with a magnet <b>402</b> for detecting the rotational position. The printed circuit board <b>801</b> is made of resin and positioned near the axial end of the shaft <b>401</b>. The printed circuit board <b>801</b> is positioned in a space between the cover <b>103</b> and a heat sink <b>601</b> that is formed integrally with the motor case <b>103</b> and made of metal. The control circuit <b>70</b> (<figref idrefs="DRAWINGS">FIG. 1</figref>) is formed on the printed circuit board <b>801</b>.
More specifically, a conductive wiring pattern is formed on the printed circuit board <b>801</b> by etching or other method, and an IC or other circuit forming the control circuit <b>70</b> is mounted on the printed circuit board <b>801</b>. The position sensor <b>73</b> (<figref idrefs="DRAWINGS">FIG. 1</figref>) is also mounted at the center of the printed circuit board <b>801</b>. The position sensor <b>73</b> detects the rotational position of the magnet <b>402</b>, that is, the rotational position of the shaft <b>401</b>. A virtual straight line obtained by extending the central axis of the shaft <b>401</b> is referred to as the rotation axis of the motor <b>30</b>.
As described above, the power circuit <b>50</b> includes the choke coil <b>52</b>, the shunt resistor <b>55</b> and two inverter circuits <b>60</b>. The choke coil <b>52</b> is formed in a ring shape as shown in <figref idrefs="DRAWINGS">FIG. 2</figref>. The ring shape has a central hole <b>523</b> as shown in <figref idrefs="DRAWINGS">FIG. 7A</figref>, for instance, so that it may be positioned to surround the shaft <b>401</b>. A heat sink <b>601</b> is formed around the choke coil <b>52</b>.
As shown in <figref idrefs="DRAWINGS">FIGS. 4 to 6</figref>, the heat sink <b>601</b> is formed on the motor case <b>103</b>. The heat sink <b>601</b> is formed on the partition wall <b>1031</b> of the motor case <b>103</b> in a raised or protruded manner from the partition wall <b>1031</b>. The heat sink <b>601</b> is formed integrally with the partition wall of the motor case <b>103</b> and extends in the axial direction of the shaft <b>401</b> toward the printed circuit board <b>801</b>. The heat sink <b>601</b> includes two columnar members <b>602</b>. Their cross sections, which are perpendicular to the axial direction of the shaft <b>401</b> are substantially trapezoidal in shape (<figref idrefs="DRAWINGS">FIG. 6</figref>). The two columnar members <b>602</b> are disposed in such a manner that the rotation axis of the motor <b>30</b> is sandwiched therebetween as exemplified in <figref idrefs="DRAWINGS">FIG. 2</figref>. Further, the columnar members <b>602</b> each have an arc portion that is cut to form an arc around the rotation axis of the motor <b>30</b>. The arc portion forms a cylindrical space at the center of the heat sink <b>601</b> to accommodate the choke coil <b>52</b> therein.
That is, the heat sink <b>601</b> is formed in a shape, which is like a thick-walled cylinder that has a side wall part <b>602</b> around the columnar space formed around the shaft <b>401</b>. Two cut parts <b>603</b> and <b>604</b> are formed in the side wall part <b>602</b> as a discontinuous part. The side wall part <b>602</b> of the heat sink <b>601</b> has six side wall surfaces <b>605</b>, which face radially outward, in the circumferential direction. An accommodation hole part <b>606</b> is formed at the radially inside part of the side wall parts <b>602</b> such that the accommodation part <b>606</b> opens toward the central cylindrical space.
Relative to the heat sink <b>601</b>, the choke coil <b>52</b> is accommodated within the cylindrical space formed in the central part of the heat sink <b>601</b>. As shown in <figref idrefs="DRAWINGS">FIG. 4</figref>, the choke coil <b>52</b> is interposed between the shaft <b>401</b> and the heat sink <b>601</b>. The choke coil <b>52</b> is spaced apart from the shaft <b>401</b> and the heat sink <b>601</b> in the radial direction with small clearances so that the choke coil <b>52</b> may be readily attached and detached.
The choke coil <b>52</b> is also spaced apart from the magnet <b>402</b> of the rotation detection sensor, so that the magnetic field generated by the choke coil <b>52</b> will not influence the magnetic field generated by the magnet <b>402</b>. To maximally suppress the influence of the magnetic field of the choke coil <b>52</b> on the magnetic field of the magnet <b>402</b>, the choke coil <b>52</b> is arranged closely to the bearing <b>105</b> in the axial direction as much as possible.
As shown in <figref idrefs="DRAWINGS">FIGS. 7A to 7C</figref>, the choke coil <b>52</b> includes a core <b>521</b> and a coil winding <b>522</b>. The core <b>521</b> is formed in a ring-shape, which has a through hole in the radially central part and a certain thickness in the central axis direction. The core <b>521</b> has an outer side surface <b>521</b><i>a </i>and an inner side surface <b>521</b><i>c </i>in parallel in the radial direction. The core <b>521</b> also has one end surface <b>521</b><i>b </i>and the other end surface <b>521</b><i>d </i>in parallel in the axial direction.
The coil winding <b>522</b> is wound about the core <b>521</b> in such a manner that its one turn starts from the one end surface <b>521</b><i>b</i>, transverses the inner side surface <b>521</b><i>c</i>, the other end surface <b>521</b><i>d </i>and the outer side surface <b>521</b><i>a</i>, and returns to the one end surface <b>521</b><i>b</i>. This turn repeats a plurality of times about the core <b>521</b> in the circumferential direction.
Both terminal ends of the coil winding <b>522</b> of the choke coil <b>52</b> are taken out outward in the radial direction through the cut part <b>603</b> formed in one heat sink <b>601</b>. Although not shown in <figref idrefs="DRAWINGS">FIGS. 2 to 6</figref>, the coil winding <b>522</b> of the choke coil <b>52</b> taken out radially outward is connected to the power cable so that the choke coil <b>52</b> is provided in the power cable as shown in <figref idrefs="DRAWINGS">FIG. 1</figref>.
As described above, the seven FETs <b>61</b> to <b>67</b>, which form the inverter circuit <b>60</b> of the power circuit <b>50</b>, are configured in three semiconductor modules, for example <b>501</b> to <b>503</b>. The drive apparatus <b>1</b> has two inverters <b>60</b> and hence a total of six semiconductor modules <b>501</b> to <b>506</b> (<figref idrefs="DRAWINGS">FIG. 2</figref>).
In case of differentiating the semiconductor modules <b>501</b> to <b>506</b>, they are referenced to as a U<b>1</b> semiconductor module <b>501</b>, a V<b>1</b> semiconductor module <b>502</b>, a W<b>1</b> semiconductor module <b>503</b>, a U<b>2</b> semiconductor module <b>504</b>, a V<b>2</b> semiconductor module <b>505</b> and a W<b>2</b> semiconductor module <b>506</b> as indicated in <figref idrefs="DRAWINGS">FIG. 2</figref>.
The U<b>1</b> semiconductor module <b>501</b> has therein the FETs <b>61</b> and <b>64</b> for the U-phase and the FET <b>67</b> for protection from reverse connection. The V<b>1</b> semiconductor module <b>502</b> has therein the FETs <b>62</b> and <b>65</b> for the V-phase. The W<b>1</b> semiconductor module has therein the FETs <b>63</b> and <b>66</b> for the W-phase. Similarly, the U<b>2</b> semiconductor module <b>504</b> has therein the FETs <b>61</b> and <b>64</b> for the U-phase and the FET <b>67</b> for protection from reverse connection. The V<b>2</b> semiconductor module <b>505</b> has therein the FETs <b>62</b> and <b>65</b> for the V-phase. The W<b>2</b> semiconductor module has therein the FETs <b>63</b> and <b>66</b> for the W-phase.
The three semiconductor modules <b>501</b>, <b>502</b> and <b>503</b> of U<b>1</b>, V<b>1</b> and W<b>1</b> form one set of the inverter circuit <b>60</b>. The other three semiconductor modules <b>504</b>, <b>505</b> and <b>506</b> of U<b>2</b>, V<b>2</b> and W<b>2</b> form the other set of inverter circuit <b>60</b>.
The three semiconductor modules <b>501</b> to <b>503</b> of U<b>1</b> to W<b>1</b> forming one set of inverter circuit <b>60</b> and the three semiconductor modules <b>504</b> to <b>506</b> of U<b>2</b> to W<b>2</b> forming the other set of inverter circuit <b>60</b> are linked by a link member <b>507</b> to form a semiconductor module unit. The link member <b>507</b> has two bus bars <b>507</b><i>a </i>and <b>507</b><i>b </i>arranged in parallel in the axial direction as shown in <figref idrefs="DRAWINGS">FIG. 5</figref>. The bus bar <b>507</b><i>a </i>is used as the power cable and located at a remote side from the partition wall <b>1031</b> of the motor case <b>103</b>. The bus bar <b>507</b><i>b </i>is used as the ground cable and arranged at a close side to the partition wall <b>1031</b> of the motor case <b>103</b>. Thus, the electric power is supplied to the semiconductor modules <b>501</b> to <b>506</b> through the bus bar set.
Although not shown, an electric connector is attached to the cover <b>104</b> so that the electric power is supplied to the link member <b>507</b> through the connector. The semiconductor modules <b>501</b> to <b>506</b> are attached to the heat sink <b>601</b>, which extends from the partition wall <b>1031</b> of the motor case <b>103</b> in the axial direction of the shaft <b>401</b>.
The heat sink <b>601</b> has a hexagonal cross section so that it has six side wall surfaces <b>605</b>, which face outward in the radial direction. Each semiconductor module <b>501</b> to <b>506</b> is provided on the side wall surface <b>605</b> in correspondence. Each of the semiconductor modules <b>501</b> to <b>506</b> is plate-shaped and extends in the direction of the surface of the molded semiconductor chip. One of the surfaces having relatively large surface area is used as the heat dissipation surface. For example, metals such as copper are exposed in the heat dissipation surface. The semiconductor modules <b>501</b> to <b>506</b> are arranged such that the heat dissipation surfaces contact the side wall surfaces <b>605</b>, respectively. The side wall surface <b>605</b> is planar, i.e. the heat sink is formed to have a planar surface at least partly on a side wall, the planer surface being linear in a plane perpendicular to the central axis of the shaft <b>41</b>, and hence the heat dissipation surface of the semiconductor module <b>501</b> to <b>506</b> is also planar correspondingly to provide a planar contact therebetwen.
Since the semiconductor modules <b>501</b> to <b>506</b> are attached to the side wall surfaces <b>605</b> of the heat sink <b>601</b>, the line perpendicular to the surface of the semiconductor chip surface is perpendicular to the central axis of the shaft <b>401</b>. The semiconductor modules <b>501</b> to <b>506</b> are thus arranged perpendicularly in such a manner that the side surfaces of the largest surface area are in parallel with the side wall surfaces <b>605</b> of the heat sink <b>601</b>. Each semiconductor module <b>501</b> to <b>506</b> and the choke coil <b>52</b> are arranged in the radial direction, that is, in the direction perpendicular to the central axis of the shaft <b>401</b>.
The semiconductor modules <b>501</b> to <b>506</b> has respective coil terminals <b>508</b> on a bottom side surface facing the partition wall <b>1031</b> of the motor case <b>103</b> as shown in <figref idrefs="DRAWINGS">FIG. 3</figref>. The lead wire <b>206</b> for supplying current to the coil <b>205</b> is taken out from the hole provided in the partition wall <b>1031</b> of the motor case <b>103</b> as described above. The lead wire <b>206</b> is clamped by and electrically connected to the coil terminal <b>508</b> of each semiconductor module <b>501</b> to <b>506</b>.
Each of the semiconductor modules <b>501</b> to <b>506</b> has six control terminals <b>509</b> and two capacitor terminals <b>510</b> at the side opposite to the motor case <b>103</b>. These terminals <b>509</b> and <b>510</b> protrude from the top side surface of the semiconductor module <b>501</b> to <b>506</b> in the axial direction opposite to the partition wall <b>1032</b> of the motor case <b>103</b>. The control terminals <b>509</b> are welded to predetermined positions of the printed circuit board <b>801</b> as shown in <figref idrefs="DRAWINGS">FIG. 4</figref>. Thus, the semiconductor modules <b>501</b> to <b>506</b> are electrically connected to the control circuit <b>70</b> to provide the circuit connection shown in <figref idrefs="DRAWINGS">FIG. 1</figref>. The capacitor terminals <b>510</b> are connected to the power cable and the ground in the semiconductor modules <b>501</b> to <b>506</b>. The capacitor terminals <b>510</b> are bent radially inward as shown in <figref idrefs="DRAWINGS">FIG. 2</figref>.
As shown in <figref idrefs="DRAWINGS">FIG. 2</figref>, six capacitors <b>701</b>, <b>702</b>, <b>703</b>, <b>704</b>, <b>705</b> and <b>706</b> are arranged in the radially inside part of the semiconductor modules <b>501</b> to <b>506</b>, that is, at the same side of the semiconductor modules <b>501</b> to <b>506</b> as the choke coil <b>52</b>. In case of differentiating the capacitors <b>701</b> to <b>706</b>, these capacitors are referred to as a U<b>1</b> capacitor <b>701</b>, a V<b>1</b> capacitor <b>702</b>, a W<b>1</b> capacitor <b>703</b>, a U<b>2</b> capacitor <b>704</b>, a V<b>2</b> capacitor <b>705</b> and a W<b>2</b> capacitor <b>706</b>. The six capacitors <b>701</b> to <b>706</b> and the corresponding six semiconductor modules <b>501</b> to <b>506</b> are arranged in the radial direction perpendicular to the central axis of the shaft <b>401</b>.
The U<b>1</b> capacitor <b>701</b>, the V<b>1</b> capacitor <b>702</b> and the W<b>1</b> capacitor <b>703</b> correspond to the capacitors <b>56</b>, <b>57</b> and <b>58</b> shown in <figref idrefs="DRAWINGS">FIG. 1</figref>, respectively. Although not shown, the U<b>2</b> capacitor <b>704</b>, the V<b>2</b> capacitor <b>705</b> and the W<b>2</b> capacitor <b>706</b> similarly correspond to the capacitors <b>56</b>, <b>57</b> and <b>58</b>, respectively.
The capacitors <b>701</b> to <b>706</b> are accommodated in the accommodation hole parts <b>606</b> of the heat sink <b>601</b> so that the capacitors <b>701</b> to <b>706</b> are located closely to the corresponding semiconductor modules <b>501</b> to <b>506</b>, respectively. Each of the capacitors <b>701</b> to <b>706</b> is formed in a cylindrical shape and arranged with its central axis being in parallel to the central axis of the shaft <b>401</b>. The capacitor terminals <b>510</b> of the semiconductor module <b>501</b> to <b>506</b> are bent in the radially inward direction such that the terminals of the capacitor <b>701</b> to <b>706</b> are directly connected to the capacitor terminals <b>510</b>.
The control circuit <b>70</b> is formed on the printed circuit board <b>801</b> as shown in <figref idrefs="DRAWINGS">FIG. 4</figref>. The printed circuit board <b>801</b> is formed a wiring pattern by etching process or the like so that integrated circuits forming the control circuit <b>70</b> are mounted. The control circuit <b>70</b> is spaced apart from the choke coil <b>52</b>, the semiconductor modules <b>501</b> to <b>507</b> and the capacitors <b>701</b> to <b>706</b>.
The drive apparatus <b>1</b> according to the first embodiment provides the following advantage.
(1) In the drive apparatus <b>1</b>, the semiconductor modules <b>501</b> to <b>506</b>, the capacitors <b>701</b> to <b>706</b> and the choke coil <b>52</b> are located in the central axis direction of the shaft <b>401</b>. The choke coil <b>52</b> is formed in a shape to allow the shaft <b>401</b> to pass therethrough. Thus, the drive apparatus <b>1</b> is reduced in size in the radial direction of the motor case <b>103</b>. The semiconductor modules <b>501</b> to <b>506</b> and the choke coil <b>52</b> are positioned in the radial direction of the shaft <b>401</b>, that is, in the direction perpendicular to the central axis of the shaft <b>401</b>. The capacitors <b>701</b> to <b>706</b> and the semiconductor modules <b>501</b> to <b>506</b> are positioned in the radial direction, that is, in the direction perpendicular to the central axis of the shaft <b>401</b>. Thus, the drive apparatus <b>1</b> is also reduced in size in the radial direction.
The motor for an EPS system has developed as shown in <figref idrefs="DRAWINGS">FIG. 8</figref>. Initially, a “separated” configuration was employed so that the motor was separate from the ECU. Then, a “mounted” configuration was frequently employed so that no wiring connections were needed. However, the “mounted” configuration was such that the electronic control unit (ECU) is housed in a case shaped like a rectangular parallelepiped and mounted outside a motor case. Next, a “built-in” configuration was employed so that the ECU was contained within a motor silhouette wherever possible. However, the use of the “built-in” configuration increased the axial physical size. As for the electronic circuit-integrated motor device <b>1</b>, however, the choke coil <b>52</b> is arranged to surround the shaft <b>401</b>. In addition, the space created by the use of such a configuration is utilized to improve the positional relationship of the semiconductor modules <b>501</b> to <b>506</b> and the capacitors <b>701</b> to <b>706</b>. The electronic circuit-integrated motor device <b>1</b> employs an “integrated” configuration, which is superior to the “built-in” configuration.
(2) The choke coil <b>52</b> is shaped to have the central hole and receive the shaft <b>401</b> of the motor part <b>30</b> therethrough. Thus, the choke coil <b>52</b> is accommodated within the electric circuit-integrated motor, that is, within the drive apparatus <b>1</b>. The shaft <b>401</b> is rotatably inserted in the central hole part of the choke coil <b>52</b>, at which heat tends to remain. The heat remaining in the central part of the choke coil <b>52</b> is transferred to the shaft <b>401</b>. Thus, radiation of heat of the choke coil <b>52</b> is promoted by the shaft <b>401</b>, which rotates.
(3) The choke coil <b>52</b> is formed annularly, that is, in the ring shape and the shaft <b>401</b> is inserted into the choke coil <b>52</b>. Since magnetic flux leaking from the coil winding <b>522</b> is attracted by the shaft <b>401</b>, the magnetic field is suppressed from leaking externally.
(4) The capacitors <b>701</b> to <b>706</b> are positioned close to the semiconductor modules <b>501</b> to <b>506</b>, respectively. The electric wiring between the semiconductor module <b>501</b> to <b>506</b> and the corresponding capacitor <b>701</b> to <b>706</b> can be shortened. The capacitors <b>701</b> to <b>706</b> are thus capable of exhibiting its performance fully. The capacitors <b>701</b> to <b>706</b> are provided for the semiconductor modules <b>501</b> to <b>506</b>, respectively, that is, in one-to-one relation. The capacitance of the capacitor <b>701</b> to <b>706</b> can be reduced to a comparatively small value. The capacitor <b>701</b> to <b>706</b> can thus be reduced in size.
(5) The drive apparatus <b>1</b> has the heat sink <b>601</b>, which extends in the axial direction of the shaft <b>401</b> from the partition wall <b>1031</b> of the motor case <b>103</b>. The semiconductor modules <b>501</b> to <b>506</b> are attached to the side wall parts <b>602</b> of the heat sink <b>601</b>, respectively. The heat of the semiconductor modules <b>501</b> to <b>506</b> is readily transferred to the heat sink <b>601</b>. Thus, the drive apparatus <b>1</b> can be used in an electric power assist system, in which a large current flows in the motor part.
(6) The heat dissipation surface of the semiconductor module <b>501</b> to <b>506</b> is in contact with the side wall surface <b>605</b> of the heat sink <b>601</b>. Thus, the heat dissipation from the semiconductor modules <b>501</b> to <b>506</b> is promoted. The side wall surface <b>605</b> is planar and hence the heat dissipation surfaces of the semiconductor modules <b>501</b> to <b>506</b> are also correspondingly planar. Thus, it is advantageous in that the side wall surfaces <b>605</b> can be machined to be flat readily.
(7) Two cut parts <b>603</b> and <b>604</b>, which form the discontinuous part, are formed on the side wall surfaces <b>602</b>. The coil winding <b>522</b> of the choke coil <b>52</b> is taken out in the radially outward direction by using the cut <b>603</b>. Thus, wiring of the choke coil <b>52</b> can be made easily.
(8) The semiconductor modules <b>501</b> to <b>506</b> and the printed circuit board <b>801</b> are arranged in parallel in the axial direction of the motor case <b>801</b>. The control terminals <b>509</b> provided on the semiconductor modules <b>501</b> to <b>506</b> are soldered to the printed circuit board <b>801</b>. Thus, it is possible to configure the drive apparatus <b>1</b> such that the control circuit <b>70</b> may be positioned independently of the semiconductor modules <b>501</b> to <b>506</b>, the capacitors <b>701</b> to <b>706</b> and the choke coil <b>52</b>. Thus, the control circuit <b>70</b> can be configured to be separated from the semiconductor modules <b>501</b> to <b>506</b>, the capacitors <b>701</b> to <b>706</b> and the choke coil <b>52</b>, in which large currents flow. As a result, the control circuit <b>70</b> can be configured to be free from heat and magnetic noise, which are generated by such large currents.
(9) The magnet <b>402</b> is fixed to one axial end of the shaft <b>401</b>, near which the printed circuit board <b>801</b> is positioned. Thus, the position sensor <b>73</b> mounted on the printed circuit board <b>801</b> detects the rotation position of the magnet <b>402</b> thereby to detect the rotation position of the shaft <b>401</b>. The rotation of the motor part <b>30</b> can be detected comparatively readily.
(10) The choke coil <b>52</b> is distanced from the magnet <b>40</b>, which forms a part of the rotation sensor, and located closely to the bearing <b>105</b> in the axial direction of the shaft <b>401</b>. Thus, the magnetic field of the choke coil <b>52</b> is suppressed from influencing the magnetic field of the magnet <b>402</b> as much as possible.
(11) The semiconductor module <b>501</b> to <b>506</b> is provided for each of the U-phase, the V-phase and the W-phase in correspondence. Specifically, the U<b>1</b> semiconductor module <b>501</b> and the U<b>2</b> semiconductor module <b>504</b> are provided in correspondence to the U-phase. The V<b>1</b> semiconductor module <b>502</b> and the V<b>2</b> semiconductor module <b>505</b> are provided in correspondence to the V-phase. The W<b>1</b> semiconductor module <b>503</b> and the W<b>2</b> semiconductor module <b>506</b> are provided in correspondence to the W-phase. Further, the semiconductor modules <b>501</b> to <b>503</b> for one set of phases U<b>1</b> to W<b>1</b> and the semiconductor modules <b>504</b> to <b>506</b> for the other set of phases U<b>2</b> to W<b>2</b> are linked in the ring shape by the link member <b>507</b> to form the semiconductor module unit. Since the semiconductor modules <b>501</b> to <b>506</b> are semiconductor module in unit of functions, the inverter circuit <b>60</b> is simplified in configuration.
Second Embodiment
According to the second embodiment, as shown in <figref idrefs="DRAWINGS">FIGS. 9</figref>, <b>10</b> and <b>11</b>A to <b>11</b>C, a drive apparatus <b>2</b> is similar to the drive apparatus <b>1</b> of the first embodiment in respect of its electrical configuration and the motor <b>30</b> shown in <figref idrefs="DRAWINGS">FIG. 1</figref>. In these figures, the cover and the printed circuit board are not shown. The drive apparatus <b>2</b> is different in respect of the power circuit <b>50</b>, particularly a choke coil <b>53</b>.
Although the choke coil <b>53</b> is positioned in the similar manner as in the first embodiment, it is configured differently. As shown in <figref idrefs="DRAWINGS">FIGS. 11A to 11C</figref>, the choke coil <b>53</b> has a cylindrical core <b>531</b> formed in a cylindrical shape, a coil winding <b>532</b> and a pair of disk parts <b>534</b>. The disk parts <b>534</b> have through holes <b>533</b> and provided at both axial ends of the cylindrical core <b>531</b>. The coil winding <b>532</b> is wound about the cylindrical core <b>531</b>.
The drive apparatus <b>2</b> also provides the advantages (1) to (12) of the drive apparatus <b>1</b>.
Third Embodiment
According to the third embodiment, as shown in <figref idrefs="DRAWINGS">FIGS. 12</figref>, <b>13</b> and <b>14</b>A to <b>14</b>C, a drive apparatus <b>3</b> is similar to the drive apparatus <b>1</b> of the first embodiment in respect of its electrical configuration and the motor <b>30</b> shown in <figref idrefs="DRAWINGS">FIG. 1</figref>. In these figures, the cover and the printed circuit board are not shown. The drive apparatus <b>3</b> is different in respect of the power circuit <b>50</b>, particularly a choke coil <b>54</b>.
Although the choke coil <b>54</b> is positioned in the similar manner as in the first embodiment, it is configured differently. As shown in <figref idrefs="DRAWINGS">FIGS. 14A to 14C</figref>, the choke coil <b>54</b> has a frame core <b>541</b> formed in a square shape and a coil winding <b>542</b>. The core <b>541</b> has a through hole <b>543</b> at its central part and thickness in the central axis direction. The core <b>541</b> has an outer side surface <b>541</b><i>a </i>and an inner side surface <b>541</b><i>c</i>, which are in parallel in the radial direction. The core <b>541</b> also has one axial end surface <b>541</b><i>b </i>and the other axial end surface <b>541</b><i>d</i>, which are in parallel in the axial direction.
As shown in <figref idrefs="DRAWINGS">FIG. 14A</figref>, the coil winding <b>542</b> is wound about the core <b>541</b><i>a </i>plurality of turns. Each turn starts from the one end surface <b>541</b><i>b </i>and returns to the one end surface <b>541</b><i>b </i>through the inner side surface <b>541</b><i>c</i>, the other end surface <b>541</b><i>d </i>and the outer side surface <b>541</b><i>a. </i>
The drive apparatus <b>3</b> also provides the advantages (1) to (12) of the drive apparatus <b>1</b>.
The drive apparatuses <b>1</b> to <b>3</b> described in the first to the third embodiments may be used not only in the power steering system but also in the other systems such as a wiper system and a valve timing control system.
Further, the drive apparatus may be implemented in other ways different from the first to the third embodiments.
Contents6
15 sheets
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| US12237739B2 | Cited by | United States of America | Applicant |
| US8471417B2 | Cited by | United States of America | Search report |
| WO2019066233A1 | Cited by | World Intellectual Property Organization (WIPO) | International search |
| US10454405B2 | Cited by | United States of America | Search report |
| US11114927B2 | Cited by | United States of America | Applicant |
| US8564996B2 | Cited by | United States of America | Search report |
| US2013285513A1 | Cited by | United States of America | Pre-grant |
| US10848042B2 | Cited by | United States of America | Applicant |
| US9320179B2 | Cited by | United States of America | Applicant |
| US2011285226A1 | Cited by | United States of America | Pre-grant |
| US11545878B2 | Cited by | United States of America | Applicant |
| US8553414B2 | Cited by | United States of America | Search report |
| US2012306299A1 | Cited by | United States of America | Pre-grant |
| US2012140539A1 | Cited by | United States of America | Pre-grant |
| JP2002345211A | Cites | Japan | Applicant |
| JP2004120941A | Cites | Japan | Applicant |
| JP2006149038A | Cites | Japan | Search report |
| US2008136265A1 | Cites | United States of America | Applicant |
| JP2008167641A | Cites | Japan | Applicant |
| JP2008198981A | Cites | Japan | Applicant |
| WO2010150527A1 | Cites | World Intellectual Property Organization (WIPO) | Applicant |
| WO2010150528A1 | Cites | World Intellectual Property Organization (WIPO) | Applicant |
| WO2010150529A1 | Cites | World Intellectual Property Organization (WIPO) | Applicant |
| WO2010150530A1 | Cites | World Intellectual Property Organization (WIPO) | Applicant |
| US6081056A | Cites | United States of America | Search report |
| US6577030B2 | Cites | United States of America | Search report |
| US6580194B2 | Cites | United States of America | Search report |
| US6998740B2 | Cites | United States of America | Search report |
| US7021418B2 | Cites | United States of America | Search report |
| US7193343B2 | Cites | United States of America | Search report |
| US7541703B2 | Cites | United States of America | Search report |
| US7898126B2 | Cites | United States of America | Search report |
| JPH0389837A | Cites | Japan | Applicant |
| JPS58141646A | Cites | Japan | Search report |
| JPO Machine Translation, Brushless Motor, JP-2006149038A, Jan. 31, 2012, http://dossier.ipdl.inpit.go.jp/text-trans.html. | Non-patent | – | Search report |
| The 3 Phase Power Resource Site, 3 Phase Motor, pp. 2/2, Jan. 31, 2012, http://www.3phasepower.org/3phasemotors.htm. | Non-patent | – | Search report |
| Japanese Office Action dated Apr. 25, 2011, issued in corresponding Japanese Application No. 2009-149645 with English Translation. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,412, Minato et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,403, Minato et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,614, Fujita et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,635, Miyachi et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,381, Iwai et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
| U.S. Appl. No. 12/822,627, Yamasaki et al, filed Jun. 24, 2010. | Non-patent | – | Applicant |
5 members in 3 offices
Priority claims4
| Document | Office | Kind | Date |
|---|---|---|---|
| 2009149645 | Japan | A | |
| 2009149645 | Japan | A | |
| 2009149645 | – | – | – |
| JP20090149645 | – | – | – |
Members5
| Document | Office | Kind | |
|---|---|---|---|
| US2010327678A1 | United States of America | A1 | |
| DE102010017514A1 | Germany | A1 | |
| JP2011010409A | Japan | A | |
| JP4811749B2 | Japan | B2 | |
| US8304942B2This record | United States of America | B2 |
57 transactions on the USPTO file
Allowed after 1 non-final rejection.
- Non-final rejections
- 1
- Final rejections
- 0
- RCEs
- 0
- Appeals
- 0
Over time
Point at a mark for the transactionTransactions
| Event | Code | |
|---|---|---|
| Expire PatentEXP. | EXP. | |
| Maintenance Fee Reminder MailedREM. | REM. | |
| Payment of Maintenance Fee, 8th Year, Large EntityM1552 | M1552 | |
| Recordation of Patent Grant MailedPGM/ | PGM/ | |
| Patent Issue Date Used in PTA CalculationAllowedPTAC | PTAC | |
| Email NotificationEML_NTR | EML_NTR | |
| Issue Notification MailedAllowedWPIR | WPIR | |
| Dispatch to FDCD1935 | D1935 | |
| Application Is Considered Ready for IssuePILS | PILS | |
| Issue Fee Payment VerifiedN084 | N084 | |
| Issue Fee Payment ReceivedIFEE | IFEE | |
| Electronic ReviewELC_RVW | ELC_RVW | |
| Email NotificationEML_NTF | EML_NTF | |
| Mail Notice of AllowanceAllowedMN/=. | MN/=. | |
| Notice of Allowance Data Verification CompletedAllowedN/=. | N/=. | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Date Forwarded to ExaminerFWDX | FWDX | |
| Response after Non-Final ActionA... | A... | |
| Electronic ReviewELC_RVW | ELC_RVW | |
| Email NotificationEML_NTF | EML_NTF | |
| Mail Non-Final RejectionNon-final rejectionMCTNF | MCTNF | |
| Non-Final RejectionNon-final rejectionCTNF | CTNF | |
| Email NotificationEML_NTR | EML_NTR | |
| Mail-Record Petition Decision of Granted to Make SpecialMP003 | MP003 | |
| Record Petition Decision of Granted to Make SpecialP003 | P003 | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Preliminary AmendmentA.PE | A.PE | |
| Petition EnteredPET. | PET. | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Reference capture on IDSRCAP | RCAP | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| PG-Pub Issue NotificationPG-ISSUE | PG-ISSUE | |
| Case Docketed to Examiner in GAUDOCK | DOCK | |
| Request for Foreign Priority (Priority Papers May Be Included)RQPR | RQPR | |
| Application Dispatched from OIPEOIPE | OIPE | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Application Is Now CompleteCOMP | COMP | |
| Sent to Classification ContractorPGPC | PGPC | |
| Filing ReceiptFLRCPT.O | FLRCPT.O | |
| Information Disclosure Statement consideredIDSC | IDSC | |
| Information Disclosure Statement (IDS) FiledM844 | M844 | |
| Information Disclosure Statement (IDS) FiledWIDS | WIDS | |
| Request from applicant for the USPTO to retrieve the Priority DocumentPDREQUST | PDREQUST | |
| Cleared by OIPE CSRL194 | L194 | |
| IFW Scan & PACR Auto Security ReviewSCAN | SCAN | |
| Initial Exam Team nnIEXX | IEXX |
13 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Lapsed due to failure to pay maintenance feeLapsedFP | FP | |
| Lapse for failure to pay maintenance feesLapsedPATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYLAPS | LAPS | |
| Information on status: patent discontinuationPATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362STCH | STCH | |
| Fee payment procedureMAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Maintenance fee paymentMAFP | MAFP | |
| Fee paymentFPAY | FPAY | |
| Fee payment procedurePAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Fee payment procedurePAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Fee payment procedurePAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Fee payment procedurePAYER NUMBER DE-ASSIGNED (ORIGINAL EVENT CODE: RMPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Fee payment procedurePAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITYFEPP | FEPP | |
| Information on status: patent grantGrantedPATENTED CASESTCF | STCF | |
| AssignmentAS | AS |
Numbers
- Publication
- 08304942
- Publication, DOCDB
- 8304942
- Publication, EPODOC
- US8304942
- Application
- 12822396
- Application, DOCDB
- 82239610
- Application, EPODOC
- US20100822396
Titles
- English
- Drive apparatus adapted to promote heat dissipation from electronic circuit integrated therein
Patent term adjustment
- A delay
- +229 daysthe office missed an examination deadline
- Net adjustment
- 229 days
Classification
- CPC, 7
- H02K3/522
- H02K11/026
- H02K2203/09
- H02K2211/03
- H02K11/33
- H02K11/05
- H02K11/028
- IPC, 2
- H02K9 00
- H02K11 00
- USPC, 3
- 310064000
- 31006800A
- 31006800R